Anchored by Jake Tapper, The Lead airs at 4 p.m. ET on CNN.
Following Scotland's historic vote on independence from the U.K.
(CNN) – The Bluefin-21 had to cut its last search for Malaysia Airlines Flight 370 short by 14 hours because the water was deeper than expected, taking the vehicle to its depth limit and forcing it to abort the mission and return to the surface.
It's just the latest challenge investigators face in this underwater search.
CNN's Tom Foreman reports.